4-Acylaminopiperidine N-oxides
The present invention relates to novel 4-acylaminopiperidine N-oxides of the general formula Ia EQU A.sup.1 B.sup.1 (Ia)
where A.sup.1 is hydrogen or an organic radical and B.sup.1 is a radical of the general formula IIa ##STR2## where
R.sup.1 -R.sup.4 are each C.sub.1 -C.sub.4 -alkyl and R.sup.1 and R.sup.2, on the one hand, and R.sup.3 and R.sup.4, on the other hand, may furthermore be bonded to form a 5-membered or 6-membered ring,
R.sup.5 is H or C.sub.1 -C.sub.4 -alkyl and
R.sup.6 is H or C.sub.1 -C.sub.18 -alkyl.
The present invention also relates to a process for the preparation of the compounds Ia, the use of the compounds for stabilizing organic materials against the harmful effect of free radicals, in particular of styrene during distillation, the joint use of the compounds Ia or Ib with aromatic nitro or nitroso compounds or substituted phenols, and liquid or solid organic materials which contain the compounds Ia.